Data Engineering & Analytics Infrastructure Topics
Data pipeline design, ETL/ELT processes, streaming architectures, data warehousing infrastructure, analytics platform design, and real-time data processing. Covers event-driven systems, batch and streaming trade-offs, data quality and governance at scale, schema design for analytics, and infrastructure for big data processing. Distinct from Data Science & Analytics (which focuses on statistical analysis and insights) and from Cloud & Infrastructure (platform-focused rather than data-flow focused).
Data Quality and Edge Case Handling
Practical skills and best practices for recognizing, preventing, and resolving real world data quality problems and edge cases in queries, analyses, and production data pipelines. Core areas include handling missing and null values, empty and single row result sets, duplicate records and deduplication strategies, outliers and distributional assumptions, data type mismatches and inconsistent formatting, canonicalization and normalization of identifiers and addresses, time zone and daylight saving time handling, null propagation in joins, and guarding against division by zero and other runtime anomalies. It also covers merging partial or inconsistent records from multiple sources, attribution and aggregation edge cases, group by and window function corner cases, performance and correctness trade offs at scale, designing robust queries and pipeline validations, implementing sanity checks and test datasets, and documenting data limitations and assumptions. At senior levels this expands to proactively designing automated data quality checks, monitoring and alerting for anomalies, defining remediation workflows, communicating trade offs to stakeholders, and balancing engineering effort against business risk.
Streaming and Real Time Systems
Fundamental concepts and design patterns for building systems that process continuous, low latency data flows and real time features. Candidates should be comfortable describing publish subscribe and event streaming paradigms, message brokers and streaming platforms, stream processing versus batch processing, ordering and partitioning strategies, backpressure and flow control, latency versus throughput trade offs, windowing and stateful stream operations, idempotency and delivery semantics, and recovery patterns such as checkpointing and replay. Practical considerations include consumer scaling, message retention, monitoring and observability, and choosing appropriate platforms and guarantees for a given workload.
Extract Transform Load and Pipeline Implementation Logic
Design and implement extract transform load pipelines and the transformation logic that powers analytics and operational features. Topics include source extraction strategies, incremental and full loads, change data capture, transformation patterns, schema migration and management, data validation and quality checks, idempotent processing, error handling and dead letter strategies, testing pipelines and data, and strategies for versioning and deploying transformation code. Emphasize implementation details that ensure correctness and maintainability of pipeline logic.
Data Pipeline Architecture
Design end to end data pipeline solutions from problem statement through implementation and operations, integrating ingestion transformation storage serving and consumption layers. Topics include source selection and connectors, ingestion patterns including batch streaming and micro batch, transformation steps such as cleaning enrichment aggregation and filtering, and loading targets such as analytic databases data warehouses data lakes or operational stores. Cover architecture patterns and trade offs including lambda kappa and micro batch, delivery semantics and fault tolerance, partitioning and scaling strategies, schema evolution and data modeling for analytic and operational consumers, and choices driven by freshness latency throughput cost and operational complexity. Operational concerns include orchestration and scheduling, reliability considerations such as error handling retries idempotence and backpressure, monitoring and alerting, deployment and runbook planning, and how components work together as a coherent maintainable system. Interview focus is on turning requirements into concrete architectures, technology selection, and trade off reasoning.